The production of beer and wine in the United States has resulted in the development of huge industries that are enjoying enormous growth. These and other alcohol-containing beverages generally require fermentation in large vats or tanks in which the ingredients, i.e. hops, barley, malt, etc., are cooked and then fermented with a bacterial culture that metabolizes the sugars and carbohydrates to produce the alcohol. However, over time, some of these components solidify and form residues or deposits and accumulate on the walls, floors and ceilings of the tanks and periodic cleaning is required.
For many years, major brewers have employed highly caustic cleaners for cleaning their production facilities. One of the more tenacious cleaning problems encountered is the development of proteinaceous "beer stone" deposits on the inner surfaces of the tanks. The difficulty in removing these residues is one of the reasons highly caustic cleaners are required. For purposes of this disclosure, "highly alkaline" refers to cleaners containing levels of about 10% to 50% alkali. Whereas this 10-50% level is actually the amount of alkali or builders incorporated in these cleaners in their concentrated form, for cleaning purposes the cleaner is diluted to an actual average use concentration of about 2.75% when mixed with water and the other ingredients.
These highly alkaline cleaners also comprise other detergents and surfactants that are necessary in order to fully clean the surfaces of these tanks. One problem that must be solved is that the proteinaceous beer deposits create very foamy conditions when solubilized and this can cause problems during cleaning. Hence, these cleaning compositions require de-foaming agents to prevent what could result in otherwise hazardous conditions due to the buildup of the foam.
Many of these detergent additives known in the industry are not stable when incorporated into the concentrated alkaline cleaners. Glucoside surfactants have been used extensively in this area but have certain drawbacks and have proven less than effective. One of the commercially available surfactants previously used in this regard is an alkoxylated alcohol (Poly-Tergent S-305-LF; Olin Corp.) which is incompatible when mixed with high levels of sodium hydroxide and most of it separates at the surface of the solution mixture. This separation problem greatly reduces the products cleaning and anti-foaming characteristics. Another potential problem that results is the cleaners contamination of the beer facilities production systems. Since the separation of the surfactant from the cleaner would result in the chemical being discharged in a pure dose when the tank is emptied, the "oily" nature of the surfactant will result in the undesirable deposit of the surfactant on production parts, the fermentation tanks, etc. If not removed, these additional deposits would lead to serious contamination problems.